As a photobase generator generating a base by being subjected to exposure, there have been known various photobase generators such as photobase generators generating primary amines or secondary amines and photobase generators generating a strong base (tertiary amines, pKa 8 to 11) and a super-strong base (guanidine, amidine and the like, pKa 11 to 13) (Patent Documents 1 to 7, Non-Patent Documents 1 to 2 and the like).
However, with regard to the photobase generators described in Patent Document 1 and Non-Patent Document 1, the basicity of the base generated is low (pKa<8), and the photobase generator is not suitable as the catalyst for a polymerization reaction or for a crosslinking reaction because the activity is low. Moreover, since these amines have an active hydrogen atom, there has been a problem that a large amount of the photobase generator is required for allowing the reaction to proceed sufficiently because these amines themselves react with one another when used in a polymerization reaction or a crosslinking reaction of epoxides and isocyanates.
Moreover, the base generators described in Patent Documents 2 to 5 and Non-Patent Document 2 and the like have a problem that the performance is low when used as photo-latent base catalysts in a polymerization reaction or a crosslinking reaction of epoxides and isocyanates since the activity to light is low, and moreover, the base generator exerts a low effect when used in combination with a photosensitizer.
Under such circumstances, there has been desired the development of a photobase generator having a catalytic activity for sufficiently curing an epoxy resin, namely, a photobase generator in which the sensitivity to light is more enhanced compared with conventional photobase generators.